Container for liquefied gases



July 7, 1925.

E. F. MUELLER ET AL' CONTAINER FOR LIQUEFIED GASES Filed July 9,

. gases, an specifically cal time.v

Patented July 7, i925.`

UNITED STATES PATENT OFFICE.

EUGENE F. HUELLER AND CLARENCE W. KANOLLVOF WASHINGTON, DISTRICT 028'` COLUIBIA.

CONTAINER FOBl mauziiiriiin'l casas.

Application led July 9, 1981. Serial No. 486,622.

To all whom #may comer/n.'

Be it known that we, EUGENE F.`MUELI.-En and CLARENCE W. KANoL'r, citizens of the United States, residing at lvashington, District of Columbia, have invented certain new and useful Improvements in Containers for occur. v

A still further object is to rovide means Liquelied Gases, cf which the following is a specification.

The invention relates in general to portable dis ensing containers for liquefied to' a container suitable for use on an aircraft for storing liquid oxygenv and suppl ing gaseous oxygen for respiration at hig altitudes.

In ,the aeronauticalv art, there is need forl a liquid-oxygen container which will supply oxygen in its gaseous state to the breathing apparatus without fail at all times when needed. It is, therefore, our purpose to provide-a container which will be absolutely safe inthis respect. 'i l Inuaccom lisliing this object, it is proposed to ma e a container which will volatilize and deliver oxygen A,at the rate required for respiration continuously from the moment that li uid oxygen is poured into-the container.. uch Ia container will function independently of human control and is thus,

adapted to. meet emergencies automatically. Furthermore, there'will be no control apparatus to get out of order and fail at a criti- Continuous `deliver of course, represents a loss of gas during ight at the lower altitudes, or atother times `when oxygen is not needed for respiration, but this disadvantage is of minor importance when the safety fac-vv tor isconsider'ed.

lt is an object also to rovide means for preventing delivery of liquid through the gas outlet under unusual conditions, such as inversion of the container.. This is'important because `any liquid oxygen reaching the aviator might cause serious injury.

A further object is to provide heat insulation for the container which will permit volatilization to the desired extent, which will withstand hard usage, and whose eilivciency will continue throughout long .use

Another obect is to-make the container Bre-proof an free from danger of explosion. `To this end, materials which could unite with the liquefied: gas to form combustible mixtures or com unds have been avoided in the selection o materials for the construction ofthe, container. Further'- more, a safety valve is-provided which will open undei excessive pressure from within'v so as to give vent to the atmosphere in an emergency before a violent explosion can for indicating the quantity o liqueed gas remaining in the container at any time. l Other objects ofthe invention will appear as the following specific description is read in connection with the accompanying drawing, which represents the container in vertica cross-section, as desi ed for use in supplyin'g ox gen 'for respiration in aviation.

n the rawing, a portable container designed for use on board an aircraft to store and supply gaseous oxygen for respiration at high altitudes is re resented by way of illustration. It is to understood, however, that we do not restrict theapplication of the inventive idea to this particular A container of the nature which will be del' scribed in detail vhereinafter should prove to be useful in other arts and in other capaci- -ties -inV the aeronautical art. For instance, a container possessing the characteristics which have been outlined briefly in the statement of the objects'of the present invention should be useful for supplying gaseous oxygen or hydrogen to internal combustion engines, especially in the case of engines employed in the propulsion of aircraft. The proposed container will be much lighter in weight and more compact than any tank for storing` an equivalent volume of oxygen or hydrogen -in might be as the storage container of oxygen apparatus for medical purposes, as means for storing liquefied hydrogen,y orv other buoyant on board an airship for inflation o the envelope, etc. i i

Beforevfdescribing the suggested,` form. which the invention ma take, it may be inted out also that various changes in the gtails of construction, substitution of materials, and other obvious modifications may the gaseous state. Other uses be made in racti without de arting from.

the sco o the invention as eined in the.V appen ed claims. l

Referrin tothe drawing by the use of instance, the side wall is cylindrical and the top and bottom walls are conical in shape. Other points of utility possessed by this particular shape will become apparent as the description progresses.

It has been stated that the principal object of the inventionV is to provide a container which Will volatilize the oxygen, or other element, atv the rate desired for delivery through the outlet. It has been discovered that this may be accomplished by insulating the container against outside heat to such an extent that just sutiicient heat to produce volatilization` at the desired rate can enter. Oneway of doing this is to provide a double walled container and to interse between the inner and outer wall memrs 2 and 3, respectively, an insulating medium possessing such heat conductingr properties that only the desired amount of heat can penetrate thecomposite wall in a unit length of time. In order to give strength to the container walls, the inner sulating material. In seeking a suitable ma- -terial for this purpose, calorox has been chosen. The advantages of calorox are low heat conductivity, low density, and the fact that it is not combustible. The use of combustible material, such as ground cork, in apparatus containing oxygen would be dangerous, for, if such material becomes satu rated with liquid oxygen by accident, the product may be a powerful` explosive. Considering the properties of the selected insulating material, the space between the wall members 2 and 3, and hence the thickness of the insulating medium, should be such av carefully calculated distance that the small quantity of heat reaching the liquefied gas through' the container walls, together with any small quantities of heat which may enter through the filling portion or other conducting .paths,`will be just suicient to cause the l1 uid to evaporate at such a rate that gas willilie evolved and delivered at approximately the rate most desirable for the intended use. In this connection, the total area of the container walls, as determined by the size and form of the container,-

bears a definite relation to the thickness of the insulating medium and* must be consldered in calculating that thickness.

The use of the inner and outer wall members 2 and 3 is necessitated by the nature of the particular insulating medium which has been adopted. These wall members give form and strength to the container, confine the insulating material, and prevent the penetration of moisturefrom the atmosphere into the insulating material. Otherwise, such moisture would condense within this material and seriously impair its insulating properties.

In order that the insulating material may be replaced by fresh material when desired, a filling openino' 5 may be provided in the outer wall memlber 3. A suitable location for this opening is at the apexof the bottom wall of the container. A threaded collar 6 may be provided at this opening for engagement with a screw cap 7 which will serve as a convenient closure for the opening.

A strong, secure base for the container may be formed by providing an extension 8l on the cylindrical portion of the outer wall member 3. This extension should project downward to a point lower than the closure cap 7, and should be beaded as at 9 to give Y increased strength to the base thus formed. lVhen the container has been transported to the desired'location for use( it may rest upon this base without danger of becoming overturned except when vthe aircraft, or other support, becomes seriously tipped or inverted in osition. Such a contingency may be provided for by securing the container to the support in any desired lnanner. It is not considered necessary to show any such securing means inthe accom anyingdrawing, since that would not ad to the disclosure of those features of the device l upon which novelty is predicated.

In order that liquefied gas may be poured into the container, a filling opening 10 may be provided in the top wall. A convenient location foi-'this opening is at the apex of this Wall, and it should extend through the inner and outer wall members and the layer of insulating material.` The 'opening may be lined by a tubular .member 11, which is preferably made of a metal of low thermal conductivity.. This mcmber 11 should be connected by airtight joints tothe inner and outer Wall members 2- and 3 of the casing. In this way, the insulating' material will be sealed effectively at this point against entrance of lmoisture from the atmosphere. A convenient way to close the filling opening l0 is to mount a threaded collar 12 on the Ytop wall of the container so as to surround Cil 1,544,854 y v I, y

reinforcing this projectingend of -the lining member by a ring 14 interposed between the same and the wall member 3, a rigid mechanical connection will be afforded between the inner and \`outer wall members 2 and 3. Otherwise, the position of thel inner wall member would be unstable. v A safety valve for preventing the occurrence of a disruptive explosion may be provided by constructing the closure cap 13 in. the manner shown in the drawing. For this,

purpose, apertures 15 have been provided in the circular wall of the cap, and ay secondary threaded flange 16 is formed inside lthe. cap so as to project intothe sleeve 12 which surrounds the filling opening of the casing. A secondary, clamping cap 17 is threaded onto the flange 16 and is adapted to clamp the marginal edge of a sealing 'member 1,8, in the form of a thin sheet of frangible material, between cap 17 and flange 16. lApertures 19 are provided inthe secondary cap for cooperation with the apertures 15 in cap 13. The sealing member 18 will prevent the escape of fluid under normal conditions. However, should the pressure Within the container rise to sucli a degree that the sealing member becomes ruptured, a vent to the atmosphere will be afforded through thev openings 15 and 19. The pressure at which the seal will become 'broken maybe regu.

lated by applying a sealing'member of predetermined thickness. The gas outlet for the container will no be described. This outlet is considered to be one of the novel features sinceit includes means for preventing the delivery of liquid with the gas, even under the most extreme conditions of practical use. In'the construction of this outlet, a tube 20 extends from the geometrical center ofthe container to one of its walls. In the present instance it has been extended to the top wall'at a point adjacent to the filling opening. At this point, the tube enters the space between the Wall members 2 and 3 and is preferably soldered `to the inner wall membenwhere'it 4penetrates the same, in order t0 effect a fiuidtight joint. The tubeextends through the insulating material to a, point preferably located at the bottom of the container, at which point it opens into the space formed within the base fiange 8 beneath the container. This space is suitable for the location of a liquid trap, so it is proposed to form such a trap by connecting fiange 8 near its base edge with the apex ofthe container bottoml by means of an imperforate wall 21.

The annulartrap thus formed is designated by the numeral22. Byconstructing the wall 21 of thinsheet metal, such as copper, heat will be conducted through the same and Harige 8 to Athe interiorv ofthe trap very readily and should cause instantaneous evaporation of any liquid entering the trap through tube 20. The trap is provided as an additional safeguard which is adapted to function under extreme conditionsA of practice,` or displacement of the inner end Y portionof tube 20, such as might result in the discharge of small quantities of liquid. The most probable cause of liquid discharge would be the production of spra near the mouth ofthe delivery tube resu ting from violent agitation of the liquid contentsof the container. A continuationl of the delivery tube is designated by the numeral 23 and shown extending from the trap through 'the outer wall member f3 of the container into the insulating medium and through the latter to an outlet 24. This outlet may be in .the form of a hose connection, as shown,

in orde'i` that connection may be made between the same and the respirator of the aviators rsonal equipment. The inner end of tu e 23 should communicate with covere by liquid within the trap except in an extreme lcase when the latter is full of liquid, or nearly so. Such an occurrence is only remotely possible and need not be given serious consideration. y

Aside from acting as an expansion chainber and trap, the space 22 serves an additional purpose. It is ,adapted to raise the temperature of the gas during its deliver to the respirator.. This has a decided a fortable for respiration than very cold gas.V

In using the container with the mouthl of the delivery tube disposed at its center, the container can be only half. full of liquefied gas at any time, Without permitting the discharge of liquid through the gas outlet. This necessitates the construction of the container of such a size that sufficient gas for a flight of maximum duration will be de indicated by the numeral 26. It will seldom be necessary to use this additional mouth, so a simple cutoff" valveA 27 may be connected with tube 25.v When thisvvalve is closed,` discharge will occur. through the mouth of tube 20alone, whereas, when the valve is open, discharge may occur through either or both mouths. iIn either event,

the presence of the valve will not prevent continuous delivery of gas at all times. It is better to use the container with only half its maximum liquid contents and to have ythe tra at such a point that it will not be y 'vant-age, in that Warmi, gas is more com- I the valve 27 closed, but it may be used more nearly completely full without much danger of delivering liquid through the outlet. Liquid will only enter the trap in case of splashing or cxtreme tipping of the container, either of which conditions is not apt to occur in successful altitude flights. The tra i will take care of quite a large amount of liquid, so delivery of liquid through the outlet is still guarded against to a conslderable degree.

In order to prevent liquefied gas from 'entering tube 25 when the container is being filled through its filling opening, a tubular shield 28 may be mounted within the llning lnember l1. This shield should v be connected with thei lining member above the mouthof tube 25 and should extenddownward past the mouth to a point near the lower end of the lining member. This shield should be smaller in diameter than the lining member from its point of attachment to the latter to its lower end, so as to furnish a conduit for gas from the-container to the mouth of tube 25.

In order that injury to the container walls may not be caused by diierenc'es in pressure between the outside atmosphere and the space containing the insulating material, it is proposed to provide a vent between the said space and the exterior of the container.

Since a direct vent through the outer wallV member would permit moisture to enter, it has been found more satisfactory to establish communication between the delivery tube and the space between wall members. This may be afforded by the tube 29, which opens into the space just mentioned, and has interrupted sections of the tube 20 connected therewith. When projection of the tube 29 through the outer wall member appears to be a desirable mechanical expedient,

its outer end may be closed by means of al screw cap, such as that indicated at 30. A screen 31 of wire gauze, or other suitable pervious material, may be positioned at the inner end of tube 29 to prevent displacement of insulating material. Some other means for connecting the delivery tube with the 'space between Wall members might be used instead of the tube 29. The latter has been chosen simply for the purpose ofA illustration of one Way of accomplishing the desired result. Tube 20 and the conducting passagesof the res irator, or other apparatus connected to tlie container outlet, will 'therefore act as a vent. Due to the length of the vent path and to the fact that this path extends through a, volume of very dry gas, no moisture can enter the insulating material through the vent.

The presence of moisture in the insulating 'material is not desired because it vimpairs its etliciency. When this material is first poured into the space between wall members 2 and 3, it may contain some moisture, but the latter will bel absorbed by the dry gas passing through the tube 29 1n contact wit-h the insulating material and will be carried oil' in theform of vapor.

It will be noted that those portions of the delivery tube which are` interposed between the inner `and outer wall members of the container extend along the inner surface of the outer wall memberthroughout almost their entire length. The reason for this arrangement is to permit warming of the delivered gas before and 'after it passes through the trap. The sheets of metal which will thereby be interposed between the gas that is being conveyed and the atmosphere will serve as means for conducting heat to the gas very rapidly. l

It may be desirable to determine the amount of liquefied gas remaining within the container from time `to time. In order to meet thisneed,agage which will give a visual indication of the liquid volume, has been provided. This gage is designated by the numeral 32 in the drawing. It may be located conveniently on the side wall of the container, as shown. The gage which has been selectedis a well-known type which is lresponsive to dierences in pressure on opposite sides of its 4diaphragm 32a. No novelty is considered to reside in this particular gage, nor in its application to the container. In the present instance, one side of the diaphragm is connectedby means of a tube 33 with the interior of the container at a point situated as high as possible. By extending tube 33 through the insulating medium to the lining memberll of the filling opening just below the point of connection between member 11 and the shieldl 28, -this may be accomplished. Another tube-34 has been extended from the other side of the gage diaphragm to the bottom of the container. A suitable construction and disposition of this tube is shown in the drawing, wherein the tube extends through the insulating medium for quite a distance and then penetrates the interior 'of the container through the inner wall member 2. As the'tube approaches the vertical axis of the container it is bent downward toward the apex of the bottom wall, to which latterl it may be secured by soldering, or otherwise, to strengthen the tube. An opening 35 is provided in tube 34 near its point of connection with the container wall so as to establish communication between the interior of the tube and the container. Owing to the conical form of the container bottom, the opening 35 will be covered by liquid' until the container is practically empty. The other tube 33 being inA communication with the gas-filled top portion of the container, the ratio -between the fluid pressures* acting upon the diathe ge sensitive to'changes in volume of the liquid. By graduating the indicator dial of the gage in terms of appropriate units of fluid measure, the gage will indicate changes in volume from the time the liquid contents `are poured into the container up to the time that these contents are exhausted sufliciently to uncover the opening 35. It has been demonstrated that, when liquefied gas is stored within the container, none of this liquid will penetrate the tube 34 through opening 35 to an extent sufficient to introduce a material error in the indications'of the gage.

A handle 36 may be attached to the container for/use in lifting or transporting the same, but it is to be understood that this handle may be omitted, or anyv other convenient means' for moving the container may be provided in practice.

It may be pointed out again, by way of emphasis, that many of the structural details described and illustrated are susceptible of alteration and even replacement by better construction which may be developed in the future. The novel` features of the device which are expressed by the suggested structure form the subject-matter of the followmg clalms.

We claim:

1. A dispensing container for liquefied gas includingmeans for causing continuous volatilization of gas at a predetermined rate, and a deliverytube having an opening disposed approximately -at the center'of the container.

2. A dispensing container for liquefiedgas including means for causing continuous volatilization. of gas at a predetermined rate, and a delivery tube havin' an opening disposed approximately at t e center `of the container, and a trap connected with the delivery tube between the said opening and its outlet adapted to prevent delivery of liquid throuh the outlet. v

3. dispensing container for liquefied gas y including means for causing continuous volatilization of gas at a predetermined rate, v

and a delivery tube havin an opening disposed approximately at t e center of the container, and an additional delivery' ,tube commumcatmg with the first mentioned delivery tube and having an opening communicating withthe interior of the container at a point proximate to its defining wall.

4. A dispensing container for liquefiedgas including means for causing continuous volatilization of gas at a predetermined rate, and a delivery tube having an opening disposed approximately at the center of the container, and an additional delivery tube communicating with the first mentioned tube and having an openingV to the defining wall of the container, and means for closing the additional tube.

5. A dispensing container for liquefied gas including means for causing continuous volatilization of gas at a predetermined rate, and a delivery tube having an outlet and an opening disposed approximately at the center of the container, and an additional de, livery tube communicating with the first mentioned tube and having an opening communicating with the interior of the container at a point proximate to the defining wall of the latter, and a liquid trap connected with the first mentioned delivery tube between its point of communication with the additional tube and the outlet.

6. A dispensing container for liquefied gas having means for causing continuous volatilization of gas at a predetermined rate embodying heat insulated walls including straight .side walls and a tapering bottom, an extension of the side walls projecting downward past the apex of the bottom to form a supporting base for the container, a liquid trap formed within the space between the said wall extension and thecontainer bottom, and a gas delivery conduit leadin from the interior of the container throu]g 1 the trap to an outlet. i a dispensing container for liquefied as including heat insulating walls, a elivery con uit leading from the mterlor of the container to an outlet, a liquidv trap disposed outside the container walls and below said container and in communication with the said conduit, said trap having walls of material possessing high thermo conductivity.

In testimony whereof we have affixed our signatures. v

EUGENE F. MUELLER. CLARENCE W. KANOLT.

disposed proximate 

